[WritingSuggestions] Update explainer to propose new attribute instead of extending autocomplete.

README.md

@@ -60,7 +60,7 @@ we move them into the [Alumni section](#alumni-) below.
 | [Pen Events](PenEvents/explainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/Pen%20Events"> ![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/Pen%20Events?label=issues)</a> | [New issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=BoCupp-Microsoft%2C+gked&labels=Pen+Events&template=pen-events.md&title=%5BPenEvents%5D+%3CTITLE+HERE%3E) | Editing |
 | [Pen Action](PenAction/explainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/Pen%20Action"> ![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/Pen%20Action?label=issues)</a> | [New issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=BoCupp-Microsoft%2C+gked&labels=Pen+Action&template=pen-action.md&title=%5Bpen-action%5D+%3CTITLE+HERE%3E) | Editing |
 | [Delayed Clipboard Rendering](DelayedClipboard/DelayedClipboardRenderingExplainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/Delayed%20Clipboard%20Rendering"> ![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/Delayed%20Clipboard%20Rendering?label=issues)</a> | [New issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=anaskim&labels=Delayed+Clipboard+Rendering&template=delayed-clipboard-rendering.md&title=%5BDelayed+Clipboard+Rendering%5D+%3CTITLE+HERE%3E) | Editing |
-| [Autocomplete Supports Edit Host Elements](AutocompleteContentEditable/explainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/AutocompleteEditHost">![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/AutocompleteEditHost?label=issues)</a> | [New Issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=bmathwig&labels=AutocompleteEditHost&template=autocomplete-edit-host.md&title=%5BAutocompleteEditHost%5D+Issue) | Editing |
+| [WritingSuggestions attribute](WritingSuggestions/explainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/WritingSuggestions">![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/WritingSuggestions?label=issues)</a> | [New Issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=sajos&labels=WritingSuggestions&template=WritingSuggestions-edit-host.md&title=%5BWritingSuggestions%5D+Issue) | HTML/Editing |
 | [Source Hashes in Stack Traces](DevTools/SourceHash/explainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/Source+hash"> ![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/Source+hash?label=issues)</a> | [New issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=robpaveza&labels=Source+hash&title=%5BSource+Hashes%5D+%3CTITLE+HERE%3E) | JavaScript |
 | [PerformanceNavigationTiming User Agent Launch](PerformanceNavigationTiming%20for%20User%20Agent%20Launch/explainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/Perf%20timing%20during%20browser%20start">![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/Perf%20timing%20during%20browser%20start?label=issues)</a> | [New issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=dylank%2C+hemingzh&labels=Perf+timing+during+browser+start&template=performance-timing-during-browser-start.md&title=%5BPerf+Timing+during+launch%5D+%3CTITLE+HERE%3E) | Performance |
 | [PerformanceNavigationTiming Protocol Launch](PerformanceNavigationTiming%20changes%20for%20protocol%20launch/explainer.md) | <a href="https://github.com/MicrosoftEdge/MSEdgeExplainers/labels/PerformanceNavigationTiming%20for%20Protocol%20Launch">![GitHub issues by-label](https://img.shields.io/github/issues/MicrosoftEdge/MSEdgeExplainers/PerformanceNavigationTiming%20for%20Protocol%20Launch?label=issues)</a> | [New issue...](https://github.com/MicrosoftEdge/MSEdgeExplainers/issues/new?assignees=atulkatti&labels=PerformanceNavigationTiming+for+Protocol+Launch&template=performancenavigationtiming-protocol-launch-timing-information.md&title=) | Performance |

WritingSuggestions/explainer.md

@@ -0,0 +1,56 @@
+# Writingsuggestions attribute to control UA-provided writing assistance
+
+Consider all sections required unless otherwise noted.
+
+Authors: [Sanket Joshi](https://github.com/sanketj)
+Previous authors: [Ben Mathwig](https://github.com/bmathwig)
+
+## Status of this Document
+
+This document is a starting point for engaging the community and standards bodies in developing collaborative solutions fit for standardization. As the solutions to problems described in this document progress along the standards-track, we will retain this document as an archive and use this section to keep the community up-to-date with the most current standards venue and content location of future work and discussions.
+
+* This document status: **Active**
+* Expected venue: [WHATWG](https://whatwg.org/)
+* Current version: [Link](#)
+
+## Introduction
+UAs are starting to provide writing suggestions to users as they type on various editable fields across the web (see the [use case](#use-case) section below). While this is
+generally useful for users, there are cases when developers may want to turn off UA-provided writing assistance, such as extensions or sites that wish to provide similar functionality on their own. To that end, this explainer proposes a solution that would allow developers to turn on/off UA-provided writing assistance.
+
+## Use Case
+A developer may use this control to take advantage of browser-provided writing assistance features like text prediction on `contenteditable` elements.
+
+### Facebook.com: Writing a post
+![Writing a post on facebook.com](facebook-post.png)
+
+### Medium.com: Drafting an article
+![Drafting an article on medium.com](medium-draft.png)
+
+### Youtube.com: Commenting on a video
+![Commenting on a video on youtube.com](youtube-video-comment.png)
+
+This control could also be used to enable additional browser-provided writing suggestions in the future. See a hypothetical example below.
+
+![Contact details suggestions example](contact-details-suggestions-example.png)
+
+A developer may also use this control to turn off browser-provided writing suggestions if they want to provide their own writing assistance tools.
+
+## Out of Scope
+1. Defining expected user agent behavior or user interface design.
+2. Styling of UA-provided writing suggestions.
+
+## Proposed Solution
+We propose the addition of a new attribute called `writingsuggestions` with values `on`/`off` that would allow developers to turn on/off browser-provided writing suggestions. This attribute will have a default state per element, as established by the UA. The attribute's state for an element can also be inherited from ancestor elements, thereby allowing developers to control this functionality at a per-element or per-document/sub-document scale.
+
+## Privacy and Security Considerations
+UAs may choose to provide users with personal settings to turn on/off writing assitance, similar to settings that are available for spellchecking. Similar to the `spellcheck` attribute, UAs must keep the values of the `writingsuggestions` attribute independent of the user's settings. Letting the user's setting influence the value of the attribute may introduce a new fingerprinting surface.
+
+## Alternative Solutions
+### Extending the `autocomplete` attribute to [editing hosts](https://html.spec.whatwg.org/multipage/interaction.html#editing-host)
+The `autocomplete` attribute is primarily designed for form fill scenarios and supports a [large number of values](https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#autofilling-form-controls:-the-autocomplete-attribute), many of which are not applicable to writing scenarios. Reasoning about how each of these values should behave on editing hosts would be complex for browser and web developers alike.
+
+### Spellcheck Attribute
+The `spellcheck` attribute is specifically designed to control the browser's spellcheck and grammar check capabilities, therefore it is not semantically appropriate for controling writing suggestions.
+
+### Text Prediction Attribute
+A `textprediction` attribute could be introduced that takes `on/off` values, allowing developers to control whether the browser's text prediction is available on a text control. Such an attribute would be specific to text prediction and would not be future proof against additional types of writing suggestions that browsers may introduce in the future.